Building mullion



Dec. 31, 1968 P. E. HELGESEN BUILDING MULLION Sheet Ora Filed Dec. 12, 1966 INVENTOR- PETER E HELGESEN,

I L I...-

Dec. 31, 1968 P. E. HELGESEN' BUILDING MULLION Sheet 3 012 Filed Dec. 12, 1966 Fia. 7

' 'NVENTOR PETE/2 E. /-/ELGESEN,

14 M wfiw United States Patent Oflice Patented Dec. 31, 1968 3,418,772 BUILDING MULLION Peter E. Helgesen, Middletown, Ohio, assignor to Armco Steel Corporation, Middletown, Ohio, a corporation of Ohio Filed Dec. 12, 1966, Ser. No. 601,022 19 Claims. (Cl. 52397) ABSTRACT OF THE DISCLOSURE A building mullion which is easy to fabricate and assemble and which is both a vertical structural element and a means for joining similar or dissimilar wall sections or panels.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to building construction and more particularly to building mullions for joining similar or dissimilar wall sections or panels.

(2) Description of the prior art A curtain wall mullion is a vertical member used to join adjacent windows, frames, structural sections, adapters, and the like. Adapters are often used with a curtain wall mullion to provide a transition between paneling material or wall sections and the curtain wall mullion. Some curtain wall mullions of the prior art are only a pair of retaining members fastened by a bolt which is perpendicular to the adjacent paneling material or wall sec tions which are to be joined. Although such prior art curtain wall mullions will exhibit a limited amount of beam strength, and can thus resist moderate windloads, they exhibit many shortcomings as complete structural units. For example, because such prior art curtain wall mullions do not provide a web member across the adjacent wall sections which are to be joined, they fail to act as structural columns and cannot resist substantial vertical loads or racking loads, the latter tending to bend the mullions horizontally in the plane of the wall in a direction parallel to the wall sections which are being joined.

With the foregoing considerations in mind, it is an object of the instant invention to provide an easily assembled building mullion which is an integral structural element and which has considerable column and beam strength so that it can support substantial loads.

It is a further object of the instant invention to provide a mullion which is capable of resisting more than moderate wind loads which tend to bend the mullion in a direction perpendicular to the wall sections or paneling material which are being joined.

It is still another object of the instant invention to provide a mullion which is capable of resisting racking loads which tend to bend the mullion horizontally in the plane of the wall in a direction parallel to the wall sections or paneling materials which are being joined.

A yet further object of the instant invention is to provide a mullion which is simple in construction, economical in manufacture, easily assembled, and otherwise well suited to the purpose for which it is designed.

Further, it is an object of the instant invention to provide a mullion which may easily be adapted to join adjacent wall sections, paneling materials, etc., of varying thicknesses.

A still additional object of the instant invention is to provide a building mullion which may be used with wall sections or panels of one width, thus alleviating the use of wall sections or panels of such varying widths which have heretofore been necessary in order to compensate for Another object of the instant invention is to provide a building mullion for the joining of a modular curtain wall to a building system of a different module without departing from the standard module of either system.

A still further object of the instant invention is to provide a building mullion which will eliminate many of the difliculties encountered when dissimilar wall sections or panels are joined.

These and other objects of the invention, which will be described in greater detail hereinafter, or which will be apparent to one skilled in the art upon reading the specification, are accomplished by that certain construction and arrangement of parts of which the following describes an exemplary embodiment.

SUMMARY OF THE INVENTION Briefly, in the practice of one embodiment of the instant invention, two adjacent mullion half sections are provided, each half section comprising a central web member, an upper U-shaped section, and a lower U-shaped section. One leg of the upper U-shaped section is longer than the other leg of that section, and the upper shaped section is integral with the central web member at the end of the shorter leg. The lower U-shaped section includes one leg which is longer than the shorter leg of the upper U-shaped section, and the central web is integral with the lower U-shaped section at the end of the longer leg. The longer leg of the upper =U-shaped section is substantially parallel with the longer leg of the lower U-shaped section, both legs being substantially normal to the central web member. The web member of each mullion half section is designed so that it will be adjacent the web member of an adjacent mullion half section. Additionally, the base of the upper U-shaped section of one mullion half section is slightly longer than the base of the upper U-shaped section of the adjacent mullion half section. This enables the longer legs of the lower 'U-shaped sections of the mullion half sections to be in alignment when a mullion section is formed, the central web members of adjacent mullion half sections being securely joined with fastening means and the longer legs of the upper U-shaped sections overlapping. Because the longer legs of the lower U-shaped sections are longer than the shorter legs of the upper U-shaped sections, they extend outwardly from the central web members beyond the base of the upper U-shaped sections. This enables adjacent wall sections or panels which are to be joined to rest on the longer legs of the lower U-shaped sections and to abut the bases of the upper U-shaped sec tions. The wall sections or panels to be joined may also rest upon gaskets placed upon the longer legs of the lower U-shaped sections. A retaining member attached by pressure exerting fasteners to the top overlapping legs of the upper U-shaped sections of the mullion section securely holds the adjacent wall or panel sections in position, urging them against the gaskets and, therefore, against the longer legs of the lower U-shaped portion of the mullion section. A lower trim cap which iits around the lower portion of the mullion section may be installed, the ends of the trim cap being engaged between the gaskets and the longer legs of the lower U-shaped section of the mullion section by the pressure applied by the retaining member to the adjacent wall or panel sections. An upper trim cap may be snapped in place over the angled ends of the retaining member after the mullion section is assembled.

In another embodiment of the instant invention the mullion half sections are identical in configuration and, therefore, when the center Web members are joined an the legs of the upper U-shaped sections overlap, the remainder of the mullion half sections forming the mullion section are out of alignment. In order to insure that the adjacent wall or panel sections to be joined will be in alignment and that they will properly rest upon the longer legs of the lower U-shaped section of the mullion section, one edge of the lower trim cap must be hemmed or formed in some way so that it will raise one gasket on one longer leg enough to compensate for the offset in the alignment When the lower trim cap is placed around the lower U-shaped sections of the mullion section.

In still another embodiment of the instant invention, a half mullion assembly, a mullion half section and an adjacent second section are provided. The mullion half section is identical in configuration with the mullion half sections previously desscribed, and the second section is similar to the reviously described mullion half sections in that its upper U-shaped section is identical with the upper U-shaped section of a mullion half section. However, central web member of the second section is not integral with a lower U-shaped section, but continues for the entire length of the half mullion assembly. The mullion half section and the second section are secured together at the central web members, the longer legs of the upper U-shaped section overlapping. The end of one wall section or panel to be joined rests upon the longer leg of the lower U-shaped section of the mullion half section, abutting the base of the upper U-shaped section of that mullion half section, being held firmly in position by a retaining member attached by pressure exerting fasteners to the top overlapping legs of the upper U- shaped sections of the half mullion assembly. Of course, this panel may also rest upon a gasket placed upon the longer leg of the lower U-shaped section of the mullion half section. The adjacent wall section or panel to be joined, the end of which is generally of an L configuration, abuts the longer central web member of the second section, the short leg of the L being contiguous with the central web member. Web reinforcing is placed over the short leg of the L to assure that the wall section or panel will be held tightly against the long central web member of the second section. A lower trim cap, one end of which is between the wall panel and the longer leg of the lower U-shaped section of the mullion half section, and the other end of which is between the long central web member of the second section and the shorter leg of the L configuration of the wall section or panel, may be used. Additionally, an upper trim cap may be utilized to snap over the angled ends of the retaining member, unless a retaining member of a unique configuration and not providing for an upper trim cap, is used.

BRIEF DESCRIPTION OF THE DRAWING Reference is made to the drawing forming a part hereof and in which:

FIGURE 1 is a perspective cross-sectional view showing a building mullion according to the instant invention being used to join an adjacent wall section with a panel section.

FIGURE 2 is an orthographic plan view of the perspective cross-section of FIGURE 1.

FIGURE 3 is a perspective view of a portion of mullion half sections showing the placement of the pres sure exerting fasteners which are used to secure a retaining member to joined mullion half sections.

FIGURES 3a and 3b are cross-sectional views of a building mullion according to the instant invention during various stages of assemblage.

FIGURE 4 is a cross-sectional view of a mullion according to the instant invention wherein the mullion half sections are identical.

FIGURE 5 is a cross-sectional view of a building mullion according to the instant invention where the mullion half sections are not identical and the mullion is used to join a door jamb and a panel section.

FIGURE 6 is a cross-sectional view of a building DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now in more detail to the drawings, and in particular to FIGURES 1 and 2, the building mullion of the instant invention will be explained in more detail. For purposes of explanation the terms upper and lower have been utilized in the specification to describe the relationship of the various components which comprise the building mullion of the instant invention. However, it will be understood that in actual practice the building mullion is in an upright position and, therefore, the terms upper and lower would correspond to the inner and outer portions of the wall, respectively.

FIGURE 1 shows generally how the building mullion 10 according to the instant invention may be used to join adjacent wall sections, panels, and the like, 11 and 12, of varying thickness. The building mullion 10 of FIGURES l and 2 includes the mullion half sections 13a and 1312 which, as will be more fully explained hereinafter, are securely fastened together to form a complete structural unit. Each mullion half section 13a and 131) comprises a central web member 14, an upper U-shaped section 15, and a lower U-shaped section 16. The upper U-shaped section 15 includes a long leg 15a, a base portion 15b and a short leg 15c, which is integrally connected to one end of the central web member 14. The lower U-shaped section 16 includes a longer leg 16a, longer than the shorter leg of the upper U-shaped section 15, a lower base 16b, and a lower flange 160. The longer leg 16a of the lower U-shaped section 16 is integrally connected to the other end of the center web member 14, the longer leg 15a of the upper U-shaped section 15 being substantially parallel to the longer leg 16a of the lower U-shaped section 16, and both legs being substantially normal to the center web member 14. The cross-section of each mullion half section 13a and 1312 are identical except for the length of the base portion 15b of the upper U-shape section 15.

The central web member 14 of each mullion half section 13a and 13b is designed so that it will lie adjacent the web member on an adjacent mullion half section and can be securely fastened thereto. The connection between the mullion half sections 130. and 13b at the web members 14 is preferable by welding, such as resistance welding, although other fastening means, such as rivets or bolts, can be employed. When the two mullion half sections 13a and 13b are joined together, they provide an integral structural element having considerable beam and column strength. The integral structural element can support vertical loads and is also capable of resisting wind loads which tend to bend the building mullion 10 in a direction perpendicular to the wall or panel sections, etc. which are being joined, and it resists racking loads which would tend to bend the building mullion 10 in a direction parallel to the wall or panel sections, etc. which are being joined.

In FIGURES 1 and 2 the building mullion 10 is being utilized to join adjacent large and small wall sections 11 and 12, respectively. The top portion of the building mullion 10 is narrower than the bottom portion so that the wall sections 11 and 12, or an adapter, such as, the adapter 21, may rest on the shoulders of the longer legs 16a of the lower U-shaped sections 16 and abut the base portions 15b of the upper U-shaped sections 15. The wall sections 11 and 12 are securely held in position through the use of the retaining member 22. The retaining member 22 is attached to the building mullion 10 by means of the pressure exerting fastener 20. FIGURE 3 shows that the longer legs 15a of the upper U-shaped sections 15 have mating apertures 23 and 23a, the aperture 23a of the underlying longer leg 15a receiving a conventional captive nut 24. The aperture 23 is longer than the aperture 23a so as to clear the tabs 24a of the captive nut 24. The retaining member 22 is held in place by means of a bolt 25 which extends therethrough and mates with the conventional captive nut 24.

It should be noted that the retaining member 22 adds structurally to the building mullion 10, enabling the building mullion to develop greater strength and to resist larger wind loads and racking loads because it is of a continuous length to match the length of the mullion 10. However, the retaining member 22 may be produced in sections if this additional strength is not required.

Additionally, it will be noted that while the building mullion of FIGURES 1 through 5 is disclosed as utilizing the bolt 25 and the captive nut 24 to secure the retaining member 22 to the longer legs a of the upper U-shaped sections 15, this fastening means is exemplary and other fastening means may be utilized.

A typical building mullion 10 according to this invention may be 3 inches by 2 /2 inches and fabricated from steel of about 16 gauge. The mullions will normally be used in lengths of about 12 feet to support vertical loads and will be spaced on 4 foot centers with adequate strength to support the wind loads.

As was explained earlier, the cross-sections of each mullion half section 13a and 13b of FIGURES 1 and 2 are identical except for the length of the upper base portions 15b of the upper U-shaped sections 5. In order to enable the longer legs 15a of the upper U-shaped sections 15 to overlap without throwing the remainder of the mullion half sections 13:: and 13b out of alignment, the base portion 15b of the overlapping mullion half section 130 must be of greater length than the base portion 15b of the mullion half section 13b in an amount substantially equal to the thickness of the overlapping longer leg 15a of the upper U-shaped section 13a. When the remainder of the mullion 10 below the overlapping legs 15a is in alignment, the adjacent wall sections 11 and 12 are properly aligned with the mullion when they rest upon the shoulders of the longer legs 16a of the lower U-shaped sections 16.

A lower trim cap 27 is provided for the lower portion of the building mullion 10. The ends 27a of the lower trim cap 27 are secured beneath the resilient gaskets 26 when the wall section 12 and the adapter 21 of the wall section 11 are tightened against the longer legs 16a of the lower U-shaped sections 16 when the retaining member is tightened. If the wall sections 11 and '12 which are to be joined happen to be the exterior wall of a building, the lower trim cap 27 will be open to the elements, in which case the resilient gaskets 26 provide a weatherproof seal. The base portions 16b and the longer leg portions 160 of the lower U-shaped sections 16 preferably make an angle 27b of about 5 degrees less than the angle 27c made by the short leg 27a and the side portion 27d of the lower trim cap 27. Thus there is only a line contact between the lower trim cap 27 and the building mullion 10, preventing wrinkling or distortion of the lower trim cap 27, particularly if the lower trim cap 27 is of a thin gauge stainless steel. Additionally, the flanges 16c are preferably not contiguous with the inside of the outer trim cap 27 for the same reason.

FIGURES 3a and 3b show the assemblage of mullion half sections 13a and 13b and the outer trim cap 27. First, the lower U-shaped portion 16 of the mullion half section 13b having the captive nuts 24 is placed through the opening in the outer trim cap 27. Next, the lower U- shaped portion 16 of the other mullion half section 13a is placed through the opening of the outer trim cap 27 so that the central web members 14 of the mullion half sections 13a and 13b will be juxtaposed. Finally, the mullion half sections 13a and 13b are pushed together, so that the central web members 14 are contiguous and the apertures 23 in the mullion half section 13a are in align- 'ment with the captive nuts 24 in the mullion half section 13b. One of the critical features of the assemblage is the length of the short leg 16c of the lower U-shaped section 16. It is desirable structurally to make the portion 16c as long as possible, but the length is limited so that the portion 160 of the mullion section 13a does not bind with the portion 16c of the mullion section 13b during the assembly. The outer edges of the longer lower legs 16a of the lower U-shaped portions 16 of the mullion half sections 1311 and 13b must provide a shoulder for the wall sections being joined and the end portions 27a of the outer trim cap 27. This, of course, will occur when the retaining member 22 is tightened against the wall sections 11 and 12, the gaskets 26, the end portions 27a of the outer trim cap 27, and the longer legs 16a of the lower U-shaped sections 16.

The angle 14a, defined by the central web member 14 and the longer legs 16a of the lower U-shaped portion 16, is preferably about 90 degrees.

The upper trim cap 28 is the last portion of the build ing mullion 10 to be installed and is snapped in place around the angled ends of the retaining member 22, the angled ends of the retaining member 22 camming the edges of the upper trim cap 28 after the pressure exerting fastener 20 has been tightened and the retaining member 22 presses against the wall sections 11 and 12.

It Will be understood that the trim caps 27 and 28 may be formed or sculptured as desired without departing from the spirit of the invention.

FIGURE 4 shows a building mullion 30 according to the instant invention in which the cross-sections of the mullion half sections 31a and 31b are identical. As was explained previously, when this is the case, and the central web members 32 of adjacent mullion half sections are joined so that the longer legs 33:: of the upper U-shaped sections 33 overlap, the remaining portion of the building mullion 30 will not be in alignment. In particular, the longer legs 34a of the lower U-shaped section 34 will not be in alignment so that the adjacent wall section 35 and the adapter 36 will not be in alignment. In order to compensate for the amount in which the mullion half sections 31a and 31b are out of alignment, one end 37 of the outer trim cap 38 is hemmed or otherwise deformed so that the edge thickness of one end 37 of the outer trim cap 38 substantially equals the thickness of the overlapping longer leg 33a of the upper U-shaped section 33.

FIGURE 5 is a cross-sectional view of a building mullion 10 according to the instant invention which is utilized to join the adjacent door jamb 39 and the wall section 40. As can be seen, two adapters 41 and 42 are held against the gaskets 43 and the longer legs 44a of the lower U-shaped sections 44 by means of the retaining member 45. The door jamb 39 is fastened to the adapter 41 and is adjacent the lower trim cap 46. The wall section is fastened to the adapter 42.

FIGURE 6 is a cross-sectional view showing a building mullion 47 according to the instant invention which is used to join an adjacent fixed sash jamb 48 and a hopper sash jamb 49.

Turning now to FIGURE 7, a half mullion assembly 50 is shown. This assembly provides for the joining of a modular curtain wall to a building system of a different module without departing from the standard module of either system. This eliminates the necessity of providing wall sections or panels of varying widths which have here tofore been required so as to compensate for the widths of building mullions when changing from one type of wall to another.

The half mullion assembly 50 of FIGURE 7 is shown joining a wall section 51 and a panel 52, one end 52a of which is of L-configuration. The mullion half section 53 is identical in cross section with the mullion half sections 13a and 13b, having an upper U-shaped section 54 and a lower U-shaped section 55 joined together by the central Web member 56. The second section 57 comprises an upper U-shaped section 58, which is identical with the upper U-shaped sections 15 of the mullion half sections 13a and 13b, and an extended central web member 59 having a lower fiange 60. One end 66a of the lower trim cap 66 may be inserted between the gasket 63 and the longer leg 55a of the lower U-shaped section 55 of the mullion half section 53, and the other end 66b inserted between the long central web member 59 of the second section 57 and the shorter leg 52b of the L-shaped end 52a of the panel 52. The lower trim cap may be inserted in position as the mullion half sections 53 and 57 are joined. The mullion half section 53 and the second section 57 are joined securely at the central web members 56 and 59, the legs 54a and 58a overlapping, so as to provide an integral structural element having considerable beam strength and which is capable of resisting both wind and racking loads. The web connection between the mullion half section 53 and the second section 54 is preferably by Welding, such as resistance welding, although other fastening means, such as rivets or bolts, can be employed.

As can be seen, the end of the wall section 51 rests upon the longer leg 55a of the lower U-shaped section 55 of the mullion half section 53, and abuts the base 54b of the upper U-shaped section 54 of that mullion half section. The wall section 51 is firmly held in place against the lower U-shaped section 55 by the retaining member 61, which is attached to the half mullion assembly 50 by means of the pressure exerting fastener 62. The pressure exerting fastener 62 is preferably a conventional captive nut and bolt arrangement which are received into mating apertures in the legs 54a and 58a, as more fully explained in connection with FIGURE 3, but any similar pressure exerting device may be employed. While the retaining member 61 differs in shape from the retaining member 22, this, of course, would not necessarily have to be the case. Retaining member 61 is shown as an example of a member which is used to terminate an interior building finish. A gasket 63 also may be provided between the short leg 66a of the trim cap and the end of the wall section 51. The L-shaped end 52a of the adjacent panel 52 abuts the longer central web member 59 of the second section 57. Web reinforcing 64 is placed over the leg 52b of the L-shaped end 52a of the panel 52. Preferably, the web reinforcing 64 is of a U-shaped cross section so as to properly space the inside of the panel 52 from the shorter leg 53]] of the second section 57. The web reinforcing 64, the short leg 52b of the L-shaped end 52a of the panel 52, and the long central web member 59 of the second section 57 are then securely fastened together by any suitable means, such as by a rivet or screw 65. An upper trim cap (not shown), similar to the upper trim cap 28 of FIGURE 2, may be snapped over the angled ends of the retaining member, if a retaining member such as the retaining member 22 is used. However, if the retaining member is designed to be used with interior molding, such as the retaining member 61 and the interior molding 67, the molding acts as the upper trim cap.

With the foregoing discussion in mind it will be understood that a building mullion of the instant invention is an integral structural column which will substantially aid in building construction. As was previously explained, this is not the case with most mullions of the prior art, which generally consist of simply a pair of retaining clips fastened by a bolt which is perpendicular to the adjacent wall sections which are being joined.

It will be understood that modifications may be made in the preferred embodiments without departing from the spirit of the invention and therefore no limitations other than those specifically set forth in the claims are intended or should be implied. For example, the shorter legs 150 of the upper U-shaped portion 15 of each mullion half section 13:: and 13b need not be substantially normal to the central web members 10 or parallel with the longer legs 16a of the lower U-shaped portion of each mullion half section 13a and 13b.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

I claim:

1. A building mullion for joining adjacent panels, frames, structural sections, adapters, and the like, which comprises:

(a) a central web member having upper and lower lateral spaced apart legs substantially normal to said web member, said upper leg being shorter in length than said lower leg and mounted at one end of said web;

(b) a retaining member substantially wider than said upper leg; and

(c) pressure exerting fasteners for mounting said retaining member on said upper leg, the edges of said member extending beyond the edges of said upper leg, and said retaining member being substantially contiguous with said upper leg for its entire length when it is in a fully tightened position;

whereby said adjacent sections to be joined abut the ends of said upper leg and are held tightly against said lower leg by said retaining member as said pressure exerting fasteners are fully tightened.

2. A building mullion according to claim 1 wherein said upper and lower legs and said retaining member are symmetrical with respect to said web.

3. A building mullion according to claim 1 wherein a lower trim cap is provided around said lower leg, the ends of said lower trim cap fitting between said adjacent sections to be joined and said lower leg, so that said trim cap is held securely in place when said pressure exerting fastener is tightened and said retaining member presses against said adjacent sections.

4. A building mullion according to claim 3 wherein an upper trim cap is provided which snaps around said retaining member, the ends of said retaining member being angled so as to cam the edges of said trim cap into position after said pressure exerting fastener has been tightened and said retaining member presses against said adjacent sections.

5. A building mullion according to claim 4 wherein resilient gaskets are provided between one end of said adjacent sections to be joined and an edge of said lower trim cap.

6. A building mullion according to claim 5 wherein said retaining member extends the entire length of said web and said upper leg.

7. A- building mullion component, which comprises a mullion half section having a central web member; an upper U-shaped section, one leg of said upper U-shaped section being shorter than the other leg of said upper U-shaped section, said upper U-shaped section being in tegral with said central web member at the end of said shorter leg; and a lower section having a first leg longer than said shorter leg of said upper U-shaped section, said first leg being integral at one end with the other end of said central web member, and a second leg which is integral at one end with the other end of said first leg and extending generally down and away from said first leg.

8. A building mullion for joining adjacent panels, frames, structural sections and the like, which comprises:

(a) a first mullion section having a central web member; an upper U-shaped section, one leg of said upper U-shaped section being shorter than the other leg of said upper U-shaped section, said upper U- shaped section being integral with said central web member at the end of said shorter leg; and a lower section having a first leg longer than said shorter leg of said upper U-shaped section, said first leg being integral at one end with the other end of said central web member, and a second leg integral at one end with the other end of said first leg and extending generally down and away from said first leg;

(b) a second mullion section having a central web member adjacent said central web member of said first mullion section, said first and'second mullion sections being securely joined together at said central web members;

(c) a retaining member associated with said first and second mullion sections of said building mullion; and

(d) pressure exerting fasteners for mounting said retaining member on said first and second mullion sections.

9. A building mullion according to claim 8 wherein said second mullion section comprises a mullion section substantially identical with said first mullion section, whereby when said central web members are securely joined together, said longer legs of said upper U-shaped sections of said first and second mullion sections overlap and said first legs of said lower sections of said first and second mullion sections extend outwardly from said central web members beyond the bases of said upper U- shaped sections of said first and second mullion sections, and said retaining member is substantially wider than said overlapping legs of said upper U-shaped sections, the edges of said retaining member extending beyond the base portions of said upper U-shaped sections, whereby said adjacent sections to be joined abut said base portions of said upper U-shaped sections and are held tightly against said first legs of said lower U-shaped sections of said first and second mullion sections by said retaining member as said pressure exerting fasteners are tightened and said retaining member presses against said adjacent panels to be joined.

10. A building mullion according to claim 9 wherein a lower trim cap is provided around said lower sections of said building mullion, the ends of said lower trim cap fitting between said adjacent sections to be joined and said first legs of said lower sections of said mullion half sections, so that said lower trim cap is held securely in place when said pressure exerting fasteners are tightened and said retaining member presses against said adjacent sections, whereby only line contact is provided between said lower trim cap and said first legs of said lower sections so as to prevent wrinkling and distortion of said lower trim cap.

11. A building mullion according to claim 10 wherein an upper trim cap is provided which snaps around said retaining member, the ends of said retaining member being angled so as to cam the edges of said upper trim cap into position after said pressure exerting fastener has been tightened and said retaining member presses against said adjacent sections.

12. A building mullion according to claim 10 wherein resilient gaskets are provided between the ends of said adjacent sections to be joined and the edges of said lower trim cap.

13. A building mullion according to claim 12 wherein the remainder of saidfirst and second mullion sections are out of alignment when said first and second sections are joined at said center web members and said longer legs of said upper U-shaped sections overlap, and a deformed edge, the thickness of which is substantially the amount of the thickness of said top overlapping longer leg of one said sections, is provided on one end of said lower trim cap between one said adjacent section to be joined and said first leg of said lower section of said other section, so that said adjacent sections to be joined are substantially aligned as they are held tightly against said first legs of said lower sections.

14. A building mullion according to claim 12 wherein the length of the base of said upper U-shaped section of said mullion section which overlaps the other is of a length which is greater than the base of the upper U- shaped section of the underlying mullion section by substantially the amount of the thickness of said top overlapping longer leg of one said upper U-shaped section, whereby the remainder of said building mullion is in alignment so that said adjacent sections to be joined are substantially aligned as they are held tightly against said first legs of said lower sections.

15. A building mullion according to claim 10 wherein said first leg and said second leg of said lower sections make an angle of about substantially 5 degrees less than the angle made by each end of said lower trim cap with the remainder of said lower trim cap.

16. A building mullion according to claim 8 wherein said second mullion section comprises an upper U-shaped section, one leg of said upper U-shaped section being shorter than the other leg of said upper U-shaped section, and said upper U-sh-aped section is integral with said central web member of said second mullion section at the end of said shorter leg, and said central web member of said second section extends beyond said central web member of said first mullion section, whereby when said central web members are securely joined together, said longer legs of said upper U-shaped sections of said first and second mullion sections overlap and said first leg of said lower section of said first mullion section extends outwardly from said central web members beyond the base of said upper U-shaped section of said first section, and said retaining member is substantially wider than said overlapping legs of said upper .U-shaped sections, one edge of said retaining member extending beyond the base portion of said upper U-shaped section of said first mullion section, whereby one said adjacent section to be joined abuts the base portion of said upper U-shaped section of said first mullion section and is held tightly against said first leg of said lower section of said first mullion section by said retaining member as said pressure exerting fastener is tightened and said retaining member presses against said one adjacent section, and one end of said other adjacent section to be joined abuts said longer center web member of said second mullion section, and a web reinforcement is provided to securely hold said end of said other adjacent section to be joined firmly against said central web member of said second section.

17. A building mullion according to claim 16 wherein the end of said other adjacent section to be joined is of L configuration and said short leg of said L portion is contiguous with said longer center web member, and said web reinforcement comprises a channel, the base of which rests firmly against said short leg of said L portion which is contiguous with said center web member of said second mullion section, and one flange of said channel is contiguous with the under side of said shorter leg of said upper U-shiaped section of said second mullion section, and the other flange of said channel is contiguous with the under side of said other adjacent section to be joined, and a fastening means is provided to secure the base of said channel, said short leg of said L portion of said other adjacent section to be joined, and said longer center web member of said second mullion section securely together.

18. A building mullion according to claim 16 wherein a lower trim cap is provided around said lower section of said first mullion section, one end of said lower trim cap fitting between one said adjacent section to be joined and said first leg of said lower section of said first mullion section, and the other end of said lower trim cap fitting between said short leg of said L portion of said other adjacent section to be joined and said longer center web member of said second mullion section, so that said lower trim cap is held securely in place when both said pressure exerting fastener is tightened causing said retaining member to press against one said adjacent section, and said fastening means joining said web reinforcing, said short leg of said other L portion of said adjacent section to be joined and said longer center web member of said second mullion section also is tightened, whereby only line contact is provided between said lower trim cap and said ad- 2,364,083 12/ 1944 Lindsay 527 18 XR jacent sections to be joined. 3,002,591 10/ 1961 Hess 52732 XR 19. A building mullion according to claim 17 wherein 3,124,222 3/ 1964 Mote 52395 XR a resilient gasket is provided between one end of one said 3,176,806 4/ 1965 Ferrell 52463 XR adjacent section to be joined and said lower trim cap 5 3,218,768 11/1965 Engholm 52463 XR resting on said first leg of said lower section of said first m llj tio BOBBY R. GAY, Primary Examiner.

References Cited A. CALVERT, Asszstan't Exammer.

UNITED STATES PATENTS 1O U.S. c1. X.R. 991,731 5/1911 MacDowney s2-397 XR 52463, 718 

